Japan, South Korea and the United States on Tuesday fully activated a trilateral real-time system for sharing data on tracking North Korean missiles, as Pyongyang confirmed that it tested a solid-fueled intercontinental ballistic missile a day earlier.

“The launch of the real-time sharing mechanism will make it possible to share missile warning data among the three countries on a continuous basis,” their defense chiefs said in a statement. “This marks a new page in defense cooperation among our three nations.”

The three partners also jointly established a multiyear plan for trilateral military drills, part of a November agreement reached by their defense chiefs as Seoul, Tokyo and Washington seek close security ties to better defend from and deter North Korea’s growing nuclear and missile threats.